Janet Scherberger, a Tampa International Airport spokeswoman, told CNN the passengers were not travelling as a group and were vomiting by the time the plane landed in Florida.

Health officials have not confirmed that water fountains at the Cleveland airport are to blame. Cleveland airport spokeswoman Michele Dynia said passengers who did get sick said they drank from the fountains at the airport.

Airport officials are looking into whether the fountains contributed to so many illnesses.

WFLA reported that the flight landed in Tampa around 3:30 p.m. and the six passengers who were ill were removed and held for medical evaluation. None were taken to the hospital, according to Scherberger, but the other 220 passengers had to wait an hour to deplane.

“During Frontier Flight 1397 from Cleveland to Tampa this afternoon, six passengers became ill. The aircraft was met by local emergency medical services upon arrival in Tampa. Those passengers displaying symptoms were evaluated by medical staff before being released. All other passengers were released after a brief holding period. The cause of the illness remains under investigation. Passenger safety is Frontier’s number one priority.”